Changing / uprating inverter

[Jamiebrookes]

I would like to change my 1600 victron inverter / charger to a victron 3 kva inverter / charger. What cables do I need to change and what size cable do I need to go up to for a 3kva 

[MtB]

 

What’s the magic word?? 

 

[Tumshie]

3 minutes ago, Mike the Boilerman said:

 

What’s the magic word?? 

 

Oh the endless possibilities 

[Alan de Enfield]

4 minutes ago, Jamiebrookes said:

I would like to change my 1600 victron inverter / charger to a victron 3 kva inverter / charger. What cables do I need to change and what size cable do I need to go up to for a 3kva 

You need to remember that the inverter is a PART of a system (you cannot put a 5 litre engine in a Mini without upgrading the engine , gear box, brakes etc)

 

You also need to review why you are doing it, is your battery bank now big enough to withstand a 300 amp draw, is your recharging system (alternator or whatever) robust enough to support the demand , then think about the cables you need.

[Jamiebrookes]

Everything needs an overhaul so I would appreciate any suggestions or help on batteries / alternator etc 

Thanks

[TheBiscuits]

Just now, Mike the Boilerman said:

 

What’s the magic word?? 

 

A/h 

[Tony Brooks]

I suppose volt drop is two words

[Jamiebrookes]

Please

[MtB]

RESULT!! 

 

[Tony Brooks]

To amplify:

 

the size of the able will depends upon the current flow and length so although we can guess the current will be about 300 amps we have no idea about the length of the two cables so can't work out the cable size required.

 

The cable size is, as others have said and implied the least of your worries. You really do need to calculate the battery bank size you need for YOUR electrical use, including the new inverter and the only person who can do that is you but first you need to calculate how many many hours you will take out of the batteries in a typical charge - discharge period. From that you can "guess" the bank size needs and also how long you will need to recharge for using a variety of alternator/charger/solar sizes. None of this is as simple as it seems but there are worked examples on my website.

 

 

Edited June 29, 2019 by Tony Brooks

[MtB]

27 minutes ago, Jamiebrookes said:

I would like to change my 1600 victron inverter / charger to a victron 3 kva inverter / charger. What cables do I need to change and what size cable do I need to go up to for a 3kva 

 

Actually to answer your question in isolation, cable size depends on the total length of the conductors. The longer they are, the fatter you need. What ‘there and back’ cable length from batts to inverter is it? 

 

Then one uses an online cable size calculator to look up what you need. 

[Jamiebrookes]

I will measure the cables over the next few days. Tony have you got a link to your site please. Thank you all  for any info

[nb Innisfree]

Voltage is another word. 

 

[Alan de Enfield]

Watt ?

[MtB]

Is that the current total?

 

[MtB]

The thing people are worried about, is 3kW is a whopping great inverter which will draw 300 Amps if you actually connect a 3kw appliance. This is engine starter motor current territory and will shag out (technical term) yer average set of domestic  batts in short order. 

 

In addition, even at rest a big inverter draws a big resting current (quiescent current) which will also drain you batts. So could you flesh out some details of why you need such a big inverter? Please? 

[Jamiebrookes]

We would like to be able to run the washing machine through the inverter especially in the summer. The washing machine is cold fill only and heats it's own water.  There is 960 watts of solar and 540 amp off battery on the boat and I know the alternator is only 70 amp connected to a beta 43.

[cuthound]

Use a thermostatic mixer valve set to 30 or 40°C to feed warm water from the calorifier into the cold water inlet on the washing machine and it shouldn't need to use its heater.

 

Then there will be no need for the big inverter.

Edited June 29, 2019 by cuthound
Clarification

[mrsmelly]

1 hour ago, Jamiebrookes said:

We would like to be able to run the washing machine through the inverter especially in the summer. The washing machine is cold fill only and heats it's own water.  There is 960 watts of solar and 540 amp off battery on the boat and I know the alternator is only 70 amp connected to a beta 43.

The small inverter will do. Buy a washing machine with cold wash capability and put hot water in the drum before closing the door. Other ways are available such as teeing the cold fill pipe into hot water with a valve to turn to cold water for rinsing etc etc.  A 3kva verter will murder your batteries unless you have a bigger alternater and always run the engine. 

[Richard10002]

I have a 2500W inverter with a total 4m run there and back to the battery bank, (nominal capacity over the years 330Ah to 450Ah. I used 95mm2 welding cable... more to do with voltage drop than Amp carrying capacity, if I recall correctly.

 

There are lots of voltage drop calculators on the web.

 

I specified 2500W so I could run a Dyson 240V vacuum cleaner. Run it for about 20mins at a time, every few months, (I have a handheld rechargeable V6 for the in between tidy ups).

[Detling]

2 hours ago, Jamiebrookes said:

 I know the alternator is only 70 amp connected to a beta 43.

I am surprised at that I thought the beta 432 came with two alternators, one 70 amp for the starter and a 110 or 130 amp for the domestics. If you fit a voltage sensative battery combiner relay then when the engine is running you could potentially have 200 amps, so needing very little from the batteries.

[mrsmelly]

Just now, Detling said:

I am surprised at that I thought the beta 432 came with two alternators, one 70 amp for the starter and a 110 or 130 amp for the domestics. If you fit a voltage sensative battery combiner relay then when the engine is running you could potentially have 200 amps, so needing very little from the batteries.

Beta 43 came with smaller alternators for the first few years. I had one with 70 amps x 2. Later ones are bigger for some reason.

[Detling]

1 minute ago, mrsmelly said:

Beta 43 came with smaller alternators for the first few years. I had one with 70 amps x 2. Later ones are bigger for some reason.

still two alternators 2x70 gives 140 amps, nearly half the 300 amp load.

[mrsmelly]

5 minutes ago, Detling said:

still two alternators 2x70 gives 140 amps, nearly half the 300 amp load.

Thing is usualy one is to the starter and the other to the domestics. Yes I spose a bit of messing can get them both working in tandem. If it were me I would get a travel power fitted. Straightforward job with all bits available for the beta 43. Recon one in first class order are available to include fitting for similar money to a 3kva victron inverter. I would keep the 1600 and add the travel power.

[Detling]

travel power will need an additional pulley and belt and I think there were problems of overloading the front bearing when a travel power was fitted, but it would be a good solution.